Pipe cleaning equipment

A pipe cleaning apparatus for a pipe having a pipe wall with a nominal inner diameter comprising:

• at least one propulsion unit for moving said apparatus within the interior of the pipe;
• and
• a cleaning unit for removing deposits from the pipe wall, said cleaning unit having an opposed hinged connection with said propulsion unit operable to permit said cleaning unit at least two degrees of freedom of movement with respect to said propulsion unit for passage of both units through bends in the pipe, said cleaning unit having an axial length and a nominal outer diameter both approximately equal to the pipe nominal inner diameter, said cleaning unit including:
• a head member;
• a plurality of rigid cutter arms each having an axial length approximately equal to the pipe nominal inner diameter as well as a first end pivotally connected to said head member at a pivotal connection so that said cutter arms are operable to pivot in a generally radial direction with respect to said head member, a peripheral edge of said cutter arms defining said cleaning unit nominal outer diameter, each of said cutter arms also having second ends distal said first ends;
• means for biasing said cutter arms radially outwardly with respect to said head member for maintaining contact between the pipe wall and said cleaning unit while said cleaning unit is maneuvered through the bends;
• and
• said head member also limiting said cleaning unit outer diameter to approximately equal to said cutter arm axial length and the pipe nominal inner diameter.